| (19) |
 |
|
(11) |
EP 1 026 512 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
07.08.2002 Bulletin 2002/32 |
| (43) |
Date of publication A2: |
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09.08.2000 Bulletin 2000/32 |
| (22) |
Date of filing: 29.12.1999 |
|
| (51) |
International Patent Classification (IPC)7: G01R 31/3185 |
|
| (84) |
Designated Contracting States: |
|
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE |
|
Designated Extension States: |
|
AL LT LV MK RO SI |
| (30) |
Priority: |
11.01.1999 JP 394299
|
| (71) |
Applicant: KOKEN CO., LTD. |
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Kita-ku, Tokyo 115-0055 (JP) |
|
| (72) |
Inventor: |
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- Nagoya,Mitsugu
Tokyo 1150055 (JP)
|
| (74) |
Representative: Ahmad, Sheikh Shakeel et al |
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David Keltie Associates, 12 New Fetter Lane
London EC4A 1AG
London EC4A 1AG (GB) |
|
| |
|
| (54) |
Test circuit for a communication element |
(57) A communication element (A) having a plurality of input-side boundary cells (1) and
output-side boundary cells (2), and a TAP circuit (3) for controlling the input and
output of data to/from said input-side and output-side boundary cells (1,2), in which
the input-side boundary cells (1) are connected in parallel to said corresponding
output-side boundary cells (2) through the TAP circuit (3), and a communication apparatus
(B) having a plurality of the communication elements (A1-A4), terminal equipments
(C1-C4) separately connected to each of said communication elements (A1-A4), for inputting
and outputting the data to/from said communication elements through said data input
and output lines (12, 13); and a host computer (11), in which the communication elements
(A1-A4) are connected in series to the host computer (11).